1. Field of the Invention
This invention relates to an improved air valve for a baby bottle to prevent colic and, more particularly, to a baby bottle having a conventional nipple at one end and a one-way air valve mounted on the bottle opposite end to admit ambient air on demand for pressure equalization while preventing leakage of the bottle contents, the valve being removable to facilitate cleaning the bottle and valve.
2. Description of the Prior Art
Baby bottles with conventional nipples have a major disadvantage in that, as the baby sucks on the nipple, the nipple collapses due to reduced air pressure in the bottle. Thus, the infant must periodically release the hold on the nipple to permit air to re-enter the bottle through the nipple hole to equalize the internal and ambient air pressure.
It has been recognized that it is desirable to permit ambient air to enter the baby bottle from a valve mechanism for pressure equalization. Examples of such prior art are found in the following U.S. Pat. Nos.: 4,685,577; 2,669,234; 2,825,479; 3,768,683; 4,401,224; and 4,545,491. U.S. Pat. No. 4,685,577 issued to Chen has an air penetrating board with several air inlet apertures therethrough and a funnel shape discharge regulating element. It has two distinct disadvantages in that fluid in the discharge regulating element, under low pressure influence from suction force, is injected into the nipple portion of the assembly, aerating the fluid by mixing. Furthermore, symmetry in the cone shaped check valve due to the annular opening will not provide enough closure in the material and would, therefore, leak. In addition, the valves will contort and leak when the twisting force motion of the end cap is applied to the "O" ring portion of the air penetrating board.
Furthermore, U.S. Pat. No. 3,768,683 discloses a solid mushroom shaped valve with a seal thereon. It has a distinct disadvantage that it will not seat well and will wobble unless the tolerance is so close that the costs would be prohibitive.
Therefore, there exists a need for a baby bottle with an improved air intake valve configuration which provides constant air pressure equalization in the bottle without undesirable leakage.